[ Merge of http://go/wvgerrit/68083 ]
Add ability to query decrypt hash support, set a hash computed over a frame
and retrieve the last error at a later point.
Bug: 34080802
Test: WV unit/integration tests. New tests added to cdm_engine_test,
libwvdrmdrmplugin_hidl_test and request_license_test.
Change-Id: I7548c8798c873a6af3e1cfc0df57c117e1e474a6